Optimisation of the paper-oil insulation of high voltage inverse current transformers using genetic algorithm

Insulation system of an instrument transformer is exposed to numerous dielectric stresses during the type tests and service life that can be hazardous if the dielectric strength of insulation is exceeded. Uniform distribution of high and low frequency stresses in the insulating system is an optimal solution. Approximately linear voltage distribution may be obtained by optimization of geometry of capacitive shields. In this paper the insulation system of the current transformer for 123 kV is optimized by the application of the genetic algorithm (GA).